New dollar general cashier, is it possible to accidentally charge a customer twice on their debit or credit card?

There were a few times I am not sure a c customer was doing it right on their end and i had to clear it and retry and they kept insisting i hit it wrong on their end and I had then put their card in again. do you think this will charge them twice? I'm not trying to get fired. there was only one other person

There were a few times I am not sure a c customer was doing it right on their end and i had to clear it and retry and they kept insisting i hit it wrong on their end and I had then put their card in again. do you think this will charge them twice? I'm not trying to get fired. there was only one other person in the store and didn't have a chance to ask.

Other answer:

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